Developer Notes

There is a back-compat issue with the new PhysX 3.4 upgrade in 4.14. All of the bone bind poses and bone actor transforms have their upper 3x3 (the orientation components) transposed in their transform matrices which causes a rotation issue. The solution for this is to use the ClothingTool or DCC plugins that match this version (the 3.4 versions) as they will not exhibit this problem. The updated ClothingTool and DCC plugins should now be available from Nvidia.

Description
  • It has no this issue if only open previous cloth assets in 4.14
  • The issue happens only if reimporting or updating the .apx or .apb and assign to the material slot
  • Reimporting both FBX skeletalmesh file and .apx files doesn't help fixing the problem. (Stuff was exported using Max PhysX plugin 3.3.3)
  • Things exported from Max PhysX plugin 3.4 seems fixed the problem, but the plugin freeze 3dsmax 2014 64bit once using Apex.....

So for now the licencee can't update any cloth after upgrading to 4.14. Also they are using 3dsMax 2014 64bit, no way to fix this issue by using newer PhysX 3.4 plugin for Max.

It has couples of other links I guess aiming the same issue here:
https://forums.unrealengine.com/showthread.php?129528-New-Cloth-mesh-to-mesh-skinning-feature-in-4-14-is-messing-up-all-my-cloth-objects

https://answers.unrealengine.com/questions/524323/apex-cloth-problem-after-upgrade-to-414.html

https://answers.unrealengine.com/questions/524403/apex-cloth-problem-in-414.html

https://answers.unrealengine.com/questions/528414/apex-clothing-sticking-to-world-origin-after-414.html

Steps to Reproduce
  • Setup a simple cloth(a plane with one bone) in 3dsmax with physx 3.3.3
  • Export both fbx and .apx
  • Import them into UE4 4.14 and assign .apx cloth file to the skeletalmesh material section
  • The result looks crazy. looks like 90 degree rotated

Have Comments or More Details?

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Won't Fix
ComponentUE - Simulation - Physics
Affects Versions4.14
Target Fix4.14.2
CreatedDec 22, 2016
ResolvedDec 22, 2016
UpdatedJun 23, 2018